Human-in-the-Loop with `MagenticOneGroupChat` loses context after handoff to user

[utkarsh-alpuria]

What happened?

Description

When implementing a Human-in-the-Loop condition with MagenticOneGroupChat, the group chat does not preserve conversation context after a handoff to the user. Instead, user input is treated as a completely new request.

This same setup works as expected with RoundRobinGroupChat — the context is preserved and the team continues the conversation correctly after user input.

---

Code to Reproduce

agent.py

from urllib import response
from autogen_agentchat.teams import MagenticOneGroupChat, RoundRobinGroupChat
import httpx
from autogen_ext.models.openai import OpenAIChatCompletionClient
from autogen_agentchat.agents import AssistantAgent
from autogen_agentchat.messages import TextMessage
from dotenv import load_dotenv
import os
import asyncio
from typing import Optional, Dict
from autogen_agentchat.conditions import HandoffTermination, TextMentionTermination
from autogen_agentchat.base import Handoff

load_dotenv()

OPENAI_API_KEY = os.getenv("OPENAI_API_KEY") 
OPENAI_MODEL_NAME = os.getenv("OPENAI_MODEL_NAME") 

httpx_client = httpx.AsyncClient(verify=False) 

model_client = OpenAIChatCompletionClient(
    model=OPENAI_MODEL_NAME, 
    api_key=OPENAI_API_KEY, 
    httpx=httpx_client
) 

class HostAgent:
    def __init__(self):
        print("Initializing HostAgent...")
        self.teams: Dict[str, MagenticOneGroupChat] = {}
        self.context_id: Optional[str] = None
    
    async def get_team(self, context_id):
        self.context_id = context_id

        if context_id in self.teams:                         
            return self.teams[context_id]                    
    
        host_agent = AssistantAgent(
            "HostAgent",
            model_client=model_client,
            handoffs=[Handoff(target="user", message="Transfer to user.")],
            system_message="You are an AI assistant agent. Your job is to answer the user's question. If you cannot complete the task, transfer to user. Otherwise, when finished, respond with 'TERMINATE'."
        )

        handoff_termination = HandoffTermination(target="user")
        text_termination = TextMentionTermination("TERMINATE")

        # Works as expected
        # team = RoundRobinGroupChat([host_agent], description="Only perform the requested task.", termination_condition=handoff_termination | text_termination)

        # Issue occurs here
        team = MagenticOneGroupChat([host_agent], model_client=model_client, max_stalls=2, description="Only perform the requested task.", termination_condition=handoff_termination | text_termination)

        self.teams[context_id] = team                         
        return team

agent_chat.py

from autogen_agentchat.ui import Console 
from agent import HostAgent 
 
session_id = '112'

async def chat_loop():
    agents = {}
    while True:
        task = input("User input : ")
       
        if session_id not in agents:
            agents[session_id] = HostAgent()  
        agent = agents[session_id]
        team = await agent.get_team(session_id)
        await Console(team.run_stream(task=task), output_stats=True)
 
if __name__ == "__main__":
    import asyncio
    asyncio.run(chat_loop())

---

Steps to Reproduce

1. Run agent_chat.py with RoundRobinGroupChat enabled in agent.py.

   • Handoff to user works as expected.
   • After user provides input, the team continues the conversation with context. ✅

2. Run the same setup but switch to MagenticOneGroupChat.

   • Handoff to user works.
   • After user provides input, the team forgets context and treats input as a completely new request. ❌

---

Expected Behavior

• After handoff, when the user provides input, the MagenticOneGroupChat should continue from the preserved state (same as RoundRobinGroupChat), instead of resetting and treating input as a new conversation.

---

Actual Behavior

• With MagenticOneGroupChat, the orchestrator restarts the workflow after handoff, ignoring prior context.

---

Terminal Logs

Working (RoundRobinGroupChat)

• Context preserved after handoff → team answers based on last message. (Logs show successful handoff + contextual response)

Not Working (MagenticOneGroupChat)

• Context lost after handoff → user input is treated as new request. (Logs show orchestrator starting fresh planning phase for "Green" input)

---

Notes

• Tried UserProxyAgent earlier, but as documented it blocks execution until user input is received, which is not suitable for longer waits.
• Documentation suggests handoff termination should allow saving and resuming team state, but this doesn’t seem to work with MagenticOneGroupChat.
• Both group chat types return the same stored team instance from memory — but only RoundRobinGroupChat preserves context.

Docs reference: Human-in-the-Loop tutorial

---

Request

Could you clarify if MagenticOneGroupChat is expected to handle handoff-based Human-in-the-Loop the same way as RoundRobinGroupChat? If so, this may be a bug in how team state is preserved after handoff.

Which packages was the bug in?

Python AgentChat (autogen-agentchat>=0.4.0)

AutoGen library version.

Python 0.7.4

Other library version.

No response

Model used

gpt-4o-mini

Model provider

OpenAI

Other model provider

No response

Python version

3.13

.NET version

None

Operating system

Windows